Mass Transfer MCQs

Question 1

Gaseous diffusivity at atmospheric pressure is of the order of __________ cm 2 /second.

Accepted Answer

1

Answer

1 to 5

Answer

5 to 10

Answer

> 10

Question 2

When both the fluids flow concurrently in an absorber, the slope of the operating line is

Accepted Answer

- ve

Answer

+ ve

Answer

1

Answer

-1

Question 3

Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature.

Accepted Answer

Wet-bulb

Answer

Dry-bulb

Answer

Dew point

Answer

Adiabatic saturation

Question 4

Molality is defined as the number of gm moles of solute per __________ of solvent.

Accepted Answer

kg

Answer

litre

Answer

gm

Answer

m 3

Question 5

In case of physical adsorption, the difference between heat of adsorption and heat of normal condensation is

Accepted Answer

Equal to the heat of wetting

Answer

Equal to the heat of formation of surface compound

Answer

Zero

Answer

Called integral heat of adsorption

Question 6

In case of gases, the binary diffusivity is proportional to (where, P = pressure)

Accepted Answer

$$\frac{1}{{	ext{P}}}$$

Answer

P

Answer

$$\frac{1}{{\sqrt {	ext{P}} }}$$

Answer

$$\sqrt {	ext{P}} $$

Question 7

Inside the distillation column, the

Accepted Answer

Driving force for the vapour flow is the pressure drop

Answer

Liquids are not always at their bubble points

Answer

Pressure increases gradually from bottom to the top of the column

Answer

None of these

Question 8

The binary diffusivity in gases does not depend upon the

Accepted Answer

None of these

Answer

Pressure

Answer

Temperature

Answer

Nature of the components

Question 9

In a counter-current liquid extractor

Accepted Answer

Only one of the liquids may be pumped at any desired rate

Answer

Both liquids flow at fixed rate

Answer

Both liquids can have any desired flow rate

Answer

Liquid's flow rate depends upon the temperature and pressure